$(document).ready(function () {
    $("#all_class_btn").mouseover(function () {
        var picture = document.getElementById("class_details");
        var showChange = document.getElementById("all_class_btn");
        enterStyle(picture);// 维持
        picture.onmouseover = function () {// 滑入弹出层
            enterStyle(picture);
            picture.onmouseout = function () {// 弹出层滑出
                getOutStyle(picture)
            }
        }
        showChange.onmouseout = function () {// 外层滑出
            getOutStyle(picture)
        }
    })
    function enterStyle(picture) {
        picture.style.display="block";

    }
    function getOutStyle(picture) {
        picture.style.display="none";

    }


});
